eliw00d

Is there any data on the turret traverse speeds of some of the more "obscure" AFVs of WWII, such as the PzKpfW 38(t)? What books or websites would you recommend for finding this type of information?

Thanks! I will definitely look these over. I feel like I've looked at this site before, but never bookmarked it. The ROF information is a nice bonus.

Thanks, guys! I figured it might, but the book didn't mention it so I wanted to make sure. The book also doesn't seem to give any formulae for German or Soviet APCR, just American 76mm and 90mm APCR (and I think British APDS). Do you guys know of any sources for those, possibly with formulae? Also, is there more information out there on how to apply BHN, high hardness, flaws, etc?

In the book, there is the following: Would lateral angle be factored in to effective resistance against HEAT, such as when angling armor? Such as impact angle = acos(cos(lateral) * cos(vertical))?

I will try those forums as well, thanks for the suggestion! I should point out that these equations are being used for a game mod, where we are trying to make a realistic armor and penetration system.

Hello again! Are there any other equations/formulas that one can use to figure out the effect of slope for different World War II ammunition (including tungsten)? Last year, I tried to adapt as much as possible from the book, but there are a lot of holes and the data I end up with does not always match the book. Any help would be much appreciated! If there are any other books or sources you guys recommend, that would help, too. Edit: I use tarrif.net as a source for penetration data, by the way.

@Thomm You are right! A slope multiplier of 1.35 @30° results in an effective penetration of 259.2mm @0°, just shy of the 260mm I am getting. But, that raises the following question: why does the book give a figure of 239mm @0° at a range of 100m? The book is a wealth of information, but unfortunately it is kind of a mess.

@Thomm No worries, I appreciate you taking the time to answer, anyways. At one point we were using a similar approach, with cosine, but after looking through this forum and the book we realized that it is not that simple for higher angles. I edited my post above with a few additional remarks, though. Edit: Also, any thoughts on where to find equivalent formulas/equations for German and Russian APCR? It's strange that the section on slope effect has no mention of either. Edit: I should point out that I took the table of a and b factors from the book and created best-fit trendlines in Excel and am using the equations from those to extrapolate data at the different angles. If there is a better way, let me know!

@Thomm I appreciate your response, but unfortunately it is not what I am looking for. I am trying to find the formula/equation used to get the figure in the book. Using the formula for shell types dependent on the T/D ratio, I am able to get figures nearly identical to those in the book (no more than 2% error in most cases). Here are the ones presented in the book: Where a and b are given in a table, depending on angle and shell type. Edit: Just realized after typing this that I must have fat-fingered 0.003787 as 0.0003787. I am now getting ~260mm, which is a bit higher than 239mm, but closer than ~149mm. Any thoughts as to the reason for this margin of error?

Hello, I recently came across a copy of WORLD WAR II BALLISTICS: Armor and Gunnery, and had a few questions. In the book, there is a section for HVAP and APDS slope multiplier equations as a function of angle. However, when I try to use the equation for 76mm HVAP, I end up with incorrect results (when compared to some of the data found here in the forums and elsewhere in the book). For example, trying to convert 100m penetration @30° (192mm) to 100m penetration @0° results in ~149mm, which is far less than the figure posted in the book (239mm). I found a post here in the forums where rexford was talking about 76mm HVAP versus Panther lower front hull, and how it had a slope multiplier of 3.3 at 55°. Using the equation given in the book, I end up with a slope multiplier of 0.85, though. So, are the HVAP/APDS equations in the book wrong? I've had no problems adapting the other formula for AP, APBC, and APC/APCBC. Also, how would one determine the slope multipliers for German, Soviet, and other APCR rounds? I couldn't find any equations for those in the book, but I may have missed it. I am trying to create a more realistic armour and penetration system for a game, and if there are any other resources besides this book that could help, please let me know! Thanks!

Thanks so much for the help, guys! This has been such a wealth of information. And yes, I do understand that everything was very dynamic in war, and that there are no single figures, but designing a mod or even a game with so many variables would take entirely too long. However, we will be giving players the choice to change distribution before a game, for more AP or HE. Keep it coming if there is more information, I really appreciate it!

Does anyone know if the other Osprey books have ammo distribution numbers, like the Sherman Medium Tank book? Are they worth getting, or are there better books out there?

As far as effectiveness, I wasn't thinking in terms of penetration - as that wouldn't be affected by range - but of accuracy and range (being affected by muzzle velocity). But that still begs the question as to whether or not HEAT was more accurate with longer barrels? I would assume so, but in practice?

@Narses Thanks for that! Funny thing is, that was my source for the Germans getting between 1-3 rounds per Panther/Tiger earlier on in the thread. As for the HEAT, I have a feeling that German HEAT rounds were probably disliked because they were fired out of short barrel weapons, which made them ineffective (lack of muzzle velocity). I wonder how the StuH42 with its HEAT rounds faired, since it had a relatively long barrel? From the data we've gathered, it seems that the M4A3(105) HEAT round was pretty decent, although not as good as conventional AP or HVAP.

Would the up-gunned (for lack of a better term) tanks have slightly more AP, as costard suggests? Tanks in question being M4A3(76)W and Sherman VC Firefly. I think someone earlier in the thread said that even though the HE was weaker in the 76mm, they still had about the same amount. Also, a friend of mine recently debated about the naming of a particular round, WP/Smoke. Did all nations use WP for their smoke rounds? Or only the Allies? And if they all did, would using WP generically suffice to describe smoke rounds of all nations? And as far as HEAT, from what I've been able to gather, it would be a smaller percentage of a vehicle or crew's distribution because it wasn't their primary duty, but more of a defensive round. Is that correct? So, for example, an M4A3(105) would have something like 70/20/10 (HE/HEAT/WP - did they have smoke rounds?).